Renal Flares Can Hike Medical Costs

Using a biologic agent to prevent flares could cut costs by more than half, according to a researcher.

SAN FRANCISCO—Patients with lupus nephritis (LN) who experience renal flares incur nearly double the direct medical costs over one year compared with those who not have flares, data suggest.

“There is a need to keep people inactive in terms of renal flare and it is very costly to let them flare and there is room here to use an expensive drug in the form of biologic agent to prevent flares,” said lead investigator Kenneth Kalunian, MD, professor of medicine at the University of California-San Diego. He presented study findings here at the American College of Rheumatology annual meeting.

Reducing the occurrence and magnitude of renal flare could result in significant medical costs savings, possibly cutting costs in half, Dr. Kalunian said. The new study is the first to examine this issue, he said, and he hopes it has a direct effect on the medical management of LN patients.

He and his colleagues obtained data for the PharMetrics Integrated Medical and Pharmaceutical Database, an integrated database of pharmacy and medical claims from approximately 85 U.S. commercial health plans. The investigators analyzed data on LN patients continuously enrolled in a commercial health plan for a minimum of 18 months between January 1, 2001 and January 1, 2006. All the patients were identified using ICD-9 diagnosis code for lupus and one of several codes for renal involvement or acute renal failure. Currently, no code exists for renal flare in LN patients, so flares were identified based on both of the following activities occurring within 14 days: a renal procedure common for LN flare, such as a 24-hour urine screen or nephrology consult, and prescription activity, including prednisone greater than 40 grams a day or new use of mycophenolate mofetil (CellCept), azathioprine, or cyclophosphamide (CTX).The investigators excluded all CNS flares by using common CNS procedures codes and/or prescription activity.

Among the 2,101 LN patients who met the criteria for study inclusion, 376 patients experienced a renal flare. On average, the direct medical costs for 12 months was $54,954 for LN patients having a renal flare compared with $29,153 for those not experiencing a flare, an average difference of $25,801. Key contributors to the increased cost for those experiencing a renal flare were lab work (136% increase in cost); physician visits (65% increase); emergency department days (83% increase); hospital days (159% increase), and medication use (87% increase).

“We were a little surprised by this. We thought it would be closer to $10,000 per patient,” Dr. Kalunian told Renal & Urology News.

“We know that patients with lupus nephritis who are stable will flare. By and large, we don't treat those patients. If we intervene with a drug that can keep them in a non-flare state, it is going to be cost-saving. Biologic agents are costly; they cost on average about $1,000 a month. Does it make economic sense? Certainly, it makes ethical sense to try to keep [patients] well, but drugs have side effects and they have costs. So, what we tried to address here are what are the real costs.”

Modulating LN with a biological agent would cost approximately $12,000 a year, which is a substantial compared with the $25,801 associated with the direct medical costs over 12 months following a flare, he noted.

An estimated 29% of LN patients will experience a flare within one year, despite good medical management, Dr. Kalunian said. Renal flares are associated with increased mortality, deterioration of renal function, and an increased risk of progression to end-stage renal disease and dialysis. In addition, renal flares are associated with the need for aggressive immunosuppressant therapies and the subsequent morbidity associated with those therapies.

The study also found that the average cost per year for LN patients, regardless of renal flare, is $34,467 per patient.